Penicillin VK (Penicillin V Potassium)

(℞) Prescription Required

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Penicillin V Potassium 250mg

Product of United Kingdom
Manufactured by: UK Various Generics
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Penicillin V Potassium 250mg
Product of United Kingdom
Manufactured by UK Various Generics
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Penicillin V Potassium 500mg

Product of New Zealand
Manufactured by: Aspen Pharmacare
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Penicillin V Potassium 500mg
Product of New Zealand
Manufactured by Aspen Pharmacare
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Penicillin V Potassium 300mg

Product of Canada
Manufactured by: AA Pharma Inc.
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Penicillin V Potassium 300mg
Product of Canada
Manufactured by AA Pharma Inc.
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Pen VK (Penicillin V Potassium) Dosage and Side Effects

Penicillin V potassium, also known as Penicillin VK, is a prescription medication used to treat mild to moderate infections of the ears, nose, throat, and skin. It is also used to treat scarlet fever and to prevent rheumatic fever. Penicillin V potassium belongs to a group of drugs called antibiotics, which stop the growth of bacteria in the body.

Proper Use of this medication

Take penicillin V potassium exactly as prescribed.

This medication comes in tablet and oral (by mouth) solution forms and may be taken 2 to 4 times a day, with or without food.

Continue to take this medication even if you feel well. Do not stop taking penicillin V potassium without talking to your doctor.

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of penicillin V potassium at the same time.

Side Effects

Serious side effects have been reported with penicillin V potassium. See “Drug Precautions” section.

Common side effects of penicillin V potassium include:

  • nausea 
  • vomiting
  • upset stomach
  • diarrhea
  • black hairy tongue

This is not a complete list of penicillin V potassium side effects. Ask your doctor or pharmacist for more information.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Warnings and Precautions

Serious side effects have been reported with penicillin V potassium including:

  • hypersensitivity (severe allergic reaction). This type of reaction may be serious and possibly fatal. These reactions are more likely to occur in those with a history of penicillin hypersensitivity and/or a history of sensitivity to multiple allergens. Tell your healthcare provider right away if you start to develop signs or symptoms of a hypersensitivity reaction, which include the following:
    • chest pain
    • swelling of the face, eyes, lips, tongue, arms, or legs
    • difficulty breathing or swallowing
    • fainting
    • rash
  • diarrhea. Diarrhea is a common problem caused by antibiotics, and it usually ends when the antibacterial is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as 2 or more months after having taken their last dose of the antibacterial. If diarrhea is severe or lasts more than 2 or 3 days, contact your doctor, as this may be a sign of an infection of the bowels.
  • superinfection. Penicillin V potassium should not be used for extended periods. Prolonged use can lead to the growth of dangerous organisms that are resistant to penicillin V potassium. Take this medication for the duration prescribed by your doctor.

Do not take penicillin V potassium if you are allergic to any of its ingredients.

Interactions with this medication

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of penicillin V potassium, there are no specific foods that you must exclude from your diet when receiving this medication.

 Inform MD

Before taking penicillin V potassium, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

  • are allergic to penicillin V potassium or to any of its ingredients
  • are allergic to similar antibiotics (penicillins, cephalosporins)
  • have a history of other allergies
  • have a history of asthma
  • have kidney problems
  • have stomach problems
  • are pregnant or breastfeeding

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Other related products

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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